capitulum (n.) Look up capitulum at Dictionary.com
used in various senses in English; Latin, literally "little head," diminutive of caput "head," also "leader, guide, chief person; summit; capital city; origin, source, spring," figuratively "life, physical life;" in writing "a division, paragraph;" of money, "the principal sum," from PIE *kaput- "head" (see head (n.)).